// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/media/session/pepper_playback_observer.h"

#include "base/command_line.h"
#include "base/metrics/histogram_macros.h"
#include "content/browser/media/session/media_session_impl.h"
#include "content/browser/media/session/pepper_player_delegate.h"
#include "content/common/frame_messages.h"
#include "ipc/ipc_message_macros.h"
#include "media/base/media_content_type.h"
#include "media/base/media_switches.h"

namespace content {

namespace {

    bool ShouldDuckFlash()
    {
        return base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
                   switches::kEnableDefaultMediaSession)
            == switches::kEnableDefaultMediaSessionDuckFlash;
    }

} // anonymous namespace

PepperPlaybackObserver::PepperPlaybackObserver(WebContents* contents)
    : contents_(contents)
{
}

PepperPlaybackObserver::~PepperPlaybackObserver()
{
    // At this point WebContents is being destructed, so it's safe to
    // call this. MediaSession may decide to send further IPC messages
    // through PepperPlayerDelegates, which might be declined if the
    // RenderViewHost has been destroyed.
    for (auto it = players_played_sound_map_.begin();
         it != players_played_sound_map_.end();) {
        const PlayerId& id = (it++)->first;
        PepperInstanceDeleted(id.first, id.second);
    }
}

void PepperPlaybackObserver::RenderFrameDeleted(
    RenderFrameHost* render_frame_host)
{
    std::vector<PlayerId> players_to_remove;
    for (auto it = players_played_sound_map_.begin();
         it != players_played_sound_map_.end();) {
        const PlayerId& id = (it++)->first;
        if (id.first == render_frame_host)
            PepperInstanceDeleted(id.first, id.second);
    }
}

void PepperPlaybackObserver::PepperInstanceCreated(
    RenderFrameHost* render_frame_host, int32_t pp_instance)
{
    PlayerId id(render_frame_host, pp_instance);
    players_played_sound_map_[id] = false;
}

void PepperPlaybackObserver::PepperInstanceDeleted(
    RenderFrameHost* render_frame_host, int32_t pp_instance)
{
    PlayerId id(render_frame_host, pp_instance);

    auto iter = players_played_sound_map_.find(id);
    if (iter == players_played_sound_map_.end())
        return;

    UMA_HISTOGRAM_BOOLEAN("Media.Pepper.PlayedSound", iter->second);
    players_played_sound_map_.erase(iter);

    PepperStopsPlayback(render_frame_host, pp_instance);
}

void PepperPlaybackObserver::PepperStartsPlayback(
    RenderFrameHost* render_frame_host, int32_t pp_instance)
{
    PlayerId id(render_frame_host, pp_instance);

    players_played_sound_map_[id] = true;

    if (players_map_.count(id))
        return;

    players_map_[id].reset(new PepperPlayerDelegate(
        render_frame_host, pp_instance));

    MediaSessionImpl::Get(contents_)->AddPlayer(
        players_map_[id].get(), PepperPlayerDelegate::kPlayerId,
        ShouldDuckFlash() ? media::MediaContentType::Pepper
                          : media::MediaContentType::OneShot);
}

void PepperPlaybackObserver::PepperStopsPlayback(
    RenderFrameHost* render_frame_host, int32_t pp_instance)
{
    PlayerId id(render_frame_host, pp_instance);

    if (!players_map_.count(id))
        return;

    MediaSessionImpl::Get(contents_)->RemovePlayer(
        players_map_[id].get(), PepperPlayerDelegate::kPlayerId);

    players_map_.erase(id);
}

} // namespace content
